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optional_interval_sample_sat

<table align="left"> <td> <a href="https://colab.research.google.com/github/google/or-tools/blob/main/examples/notebook/sat/optional_interval_sample_sat.ipynb">Run in Google Colab</a> </td> <td> <a href="https://github.com/google/or-tools/blob/main/ortools/sat/samples/optional_interval_sample_sat.py">View source on GitHub</a> </td> </table>

First, you must install ortools package in this colab.

python

%pip install ortools

Code sample to demonstrates how to build an optional interval.

python

from ortools.sat.python import cp_model


def optional_interval_sample_sat():
    """Showcases how to build optional interval variables."""
    model = cp_model.CpModel()
    horizon = 100

    # An interval can be created from three affine expressions.
    start_var = model.new_int_var(0, horizon, "start")
    duration = 10  # Python cp/sat code accept integer variables or constants.
    end_var = model.new_int_var(0, horizon, "end")
    presence_var = model.new_bool_var("presence")
    interval_var = model.new_optional_interval_var(
        start_var, duration, end_var + 2, presence_var, "interval"
    )

    print(f"interval = {repr(interval_var)}")

    # If the size is fixed, a simpler version uses the start expression and the
    # size.
    fixed_size_interval_var = model.new_optional_fixed_size_interval_var(
        start_var, 10, presence_var, "fixed_size_interval_var"
    )
    print(f"fixed_size_interval_var = {repr(fixed_size_interval_var)}")

    # A fixed interval can be created using the same API.
    fixed_interval = model.new_optional_fixed_size_interval_var(
        5, 10, presence_var, "fixed_interval"
    )
    print(f"fixed_interval = {repr(fixed_interval)}")


optional_interval_sample_sat()